Merge branch 'feat/94-add-get-lobby-list-command-on-server-side' into 'main'

Feat/94 add get lobby list command on server side

Closes #94

See merge request cs108-fs26/Gruppe-13!105

documents/docs/networking/commands/protocol-document.md

@@ -50,6 +50,12 @@ This document describes the protocol for client-server communication in our appl
     - [Error Response](#error-response-6)
     - [Example Request](#example-request-4)
     - [Example Response](#example-response-4)
+  - [GET_LOBBY_LIST command](#get_lobby_list-command)
+    - [Required pre-execution checks](#required-pre-execution-checks)
+    - [Request Parameters](#request-parameters)
+    - [Success Response](#success-response)
+    - [Example Request](#example-request)
+    - [Example Response](#example-response)
   - [SEND_MESSAGE command](#send_message-command)
     - [Required pre-execution checks](#required-pre-execution-checks)
     - [Request Parameters](#request-parameters)
@@ -535,6 +541,60 @@ END
 END
 ```
 
+## GET_LOBBY_LIST command
+
+The `GET_LOBBY_LIST` command requests the server to return a list of currently available lobbies with basic metadata.
+
+### Required pre-execution checks
+None.
+
+### Request Parameters
+No parameters.
+
+### Implementation notes
+
+- Parser: `GetLobbyListParser` — creates `GetLobbyListRequest` (no parameters).
+- Handler: `GetLobbyListHandler` — queries `LobbyManager#getAllLobbies()` and returns `GetLobbyListResponse`.
+- Response: `GetLobbyListResponse` — builds a `LOBBIES` collection with repeated `LOBBY` blocks containing `ID`, `NAME`, `PLAYER_COUNT`.
+
+### Success Response
+
+The response contains a `LOBBIES` collection with nested `LOBBY` entries.
+
+Example response structure:
+
+```
++OK
+  LOBBIES
+    LOBBY
+      ID=1
+      NAME=Room 1
+      PLAYER_COUNT=2
+    END
+    LOBBY
+      ID=2
+      NAME=Room 2
+      PLAYER_COUNT=3
+    END
+  END
+END
+```
+
+### Example Request
+
+```
+GET_LOBBY_LIST
+```
+
+### Example Response (error)
+
+```
+-ERR
+  CODE=NO_LOBBIES_AVAILABLE
+  MESSAGE=No lobbies available
+END
+```
+
 ## GET_LOBBY_STATUS command
 
 The `GET_LOBBY_STATUS` command requests the server to return the current state of a lobby, including the list of players and their ready state.

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/ServerApp.java

@@ -140,6 +140,20 @@ public class ServerApp {
         commandRouter.register(
                 ListUsersRequest.class, new ListUsersHandler(responseDispatcher, userRegistry));
 
+        // GET_LOBBY_LIST registration
+        parserDispatcher.register(
+                "GET_LOBBY_LIST",
+                new ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
+                        .GetLobbyListParser());
+        commandRouter.register(
+                ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
+                        .GetLobbyListRequest.class,
+                (ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandHandler<
+                                ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby
+                                        .get_lobby_list.GetLobbyListRequest>)
+                        new ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
+                                .GetLobbyListHandler(responseDispatcher, lobbyManager));
+
                 // GET_LOBBY_STATUS registration
         parserDispatcher.register(
                 "GET_LOBBY_STATUS",
@@ -155,6 +169,7 @@ public class ServerApp {
                                 .get_lobby_status.GetLobbyStatusHandler(
                                 responseDispatcher, lobbyManager, userRegistry));
 
+
         // JOIN_LOBBY registration
         parserDispatcher.register(
                 "JOIN_LOBBY",

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_list/GetLobbyListHandler.java

@@ -0,0 +1,28 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.LobbyManager;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandHandler;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatcher;
+import java.util.Collection;
+
+/**
+ * Handler for the `GET_LOBBY_LIST` command.
+ *
+ * <p>Queries the {@link LobbyManager} for all available lobbies and dispatches a {@link
+ * GetLobbyListResponse} containing basic metadata for each lobby (`ID`, `NAME`, `PLAYER_COUNT`).
+ */
+public class GetLobbyListHandler extends CommandHandler<GetLobbyListRequest> {
+    private final LobbyManager lobbyManager;
+
+    public GetLobbyListHandler(ResponseDispatcher responseDispatcher, LobbyManager lobbyManager) {
+        super(responseDispatcher);
+        this.lobbyManager = lobbyManager;
+    }
+
+    @Override
+    public void execute(GetLobbyListRequest request) {
+        Collection<ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.Lobby> l =
+                lobbyManager.getAllLobbies();
+        responseDispatcher.dispatch(new GetLobbyListResponse(request.getContext(), l));
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_list/GetLobbyListParser.java

@@ -0,0 +1,17 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParser;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
+
+/**
+ * Parser for the `GET_LOBBY_LIST` command.
+ *
+ * <p>Parses the incoming primitive request and produces a {@link GetLobbyListRequest}. This command
+ * takes no parameters.
+ */
+public class GetLobbyListParser implements CommandParser<GetLobbyListRequest> {
+    @Override
+    public GetLobbyListRequest parse(PrimitiveRequest primitiveRequest) {
+        return new GetLobbyListRequest(primitiveRequest.context());
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_list/GetLobbyListRequest.java

@@ -0,0 +1,15 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+
+/**
+ * Request object for the `GET_LOBBY_LIST` command.
+ *
+ * <p>Contains only the request context; this command does not require parameters.
+ */
+public class GetLobbyListRequest extends Request {
+    public GetLobbyListRequest(RequestContext context) {
+        super(context);
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_list/GetLobbyListResponse.java

@@ -0,0 +1,37 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.Lobby;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.SuccessResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
+import java.util.Collection;
+
+/**
+ * Success response for `GET_LOBBY_LIST`.
+ *
+ * <p>Builds a `LOBBIES` collection with repeated `LOBBY` blocks containing `ID`, `NAME` and
+ * `PLAYER_COUNT`.
+ */
+public class GetLobbyListResponse extends SuccessResponse {
+    public GetLobbyListResponse(RequestContext context, Collection<Lobby> lobbies) {
+        super(
+                context,
+                ResponseBody.builder()
+                        .block(
+                                "LOBBIES",
+                                lobbies_block -> {
+                                    for (Lobby lobby : lobbies) {
+                                        lobbies_block.block(
+                                                "LOBBY",
+                                                lb -> {
+                                                    lb.param("ID", lobby.getId().value());
+                                                    lb.param("NAME", lobby.getName());
+                                                    lb.param(
+                                                            "PLAYER_COUNT",
+                                                            lobby.getPlayerNames().size());
+                                                });
+                                    }
+                                })
+                        .build());
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_status/GetLobbyStatusHandler.java

@@ -8,14 +8,7 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.ErrorRes
 import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatcher;
 import java.util.Optional;
 
-/**
- * Handler for the `GET_LOBBY_STATUS` command.
- *
- * <p>Resolves the target lobby either by the optional `ID` parameter or by `USERNAME`. If both are
- * omitted the handler requires the session to be associated with a logged-in user (see the inline
- * pre-execution check). On success a {@link GetLobbyStatusResponse} is dispatched, otherwise an
- * {@link ErrorResponse} with code `LOBBY_NOT_FOUND` is sent.
- */
+/** Handler for GET_LOBBY_STATUS: returns lobby details and player list. */
 public class GetLobbyStatusHandler extends CommandHandler<GetLobbyStatusRequest> {
     private final LobbyManager lobbyManager;
     private final UserRegistry userRegistry;
@@ -53,22 +46,10 @@ public class GetLobbyStatusHandler extends CommandHandler<GetLobbyStatusRequest>
 
     @Override
     public void execute(GetLobbyStatusRequest request) {
-        // Resolve username from request or session when no explicit ID/USERNAME
-        // provided
-        String targetUsername = request.getUsername();
-        if (targetUsername == null) {
-            var maybeUser = userRegistry.getBySessionId(request.getSessionId());
-            if (maybeUser.isPresent()) {
-                targetUsername = maybeUser.get().getName();
-            }
-        }
-
         var lobby =
                 (request.getId() != null)
                         ? lobbyManager.getLobby(LobbyId.of(request.getId()))
-                        : (targetUsername != null
-                                ? lobbyManager.getLobbyByUsername(targetUsername)
-                                : null);
+                        : lobbyManager.getLobbyByUsername(request.getUsername());
 
         if (lobby == null) {
             responseDispatcher.dispatch(

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_status/GetLobbyStatusParser.java

@@ -5,21 +5,6 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Primitive
 import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor.RequestParameterAccessor;
 
 public class GetLobbyStatusParser implements CommandParser<GetLobbyStatusRequest> {
-    /**
-     * Parse the incoming primitive request into a {@link GetLobbyStatusRequest}.
-     *
-     * <p>Supported optional parameters:
-     *
-     * <ul>
-     *   <li>`ID` (int) — numeric lobby id to query
-     *   <li>`USERNAME` (String) — username to lookup the lobby for
-     * </ul>
-     *
-     * If both are omitted the handler may require a logged-in session.
-     *
-     * @param primitiveRequest raw request containing parameters and context
-     * @return parsed {@link GetLobbyStatusRequest}
-     */
     @Override
     public GetLobbyStatusRequest parse(PrimitiveRequest primitiveRequest) {
         RequestParameterAccessor accessor =

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_status/GetLobbyStatusRequest.java

@@ -7,25 +7,16 @@ public class GetLobbyStatusRequest extends Request {
     private final Integer id;
     private final String username;
 
-    /**
-     * Create a new GetLobbyStatusRequest.
-     *
-     * @param context request context (session id, source, etc.)
-     * @param id optional numeric lobby id to query, or null
-     * @param username optional username to query the lobby for, or null
-     */
     public GetLobbyStatusRequest(RequestContext context, Integer id, String username) {
         super(context);
         this.id = id;
         this.username = username;
     }
 
-    /** Returns the optional lobby id. */
     public Integer getId() {
         return id;
     }
 
-    /** Returns the optional username. */
     public String getUsername() {
         return username;
     }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/lobby/get_lobby_status/GetLobbyStatusResponse.java

@@ -5,19 +5,8 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestCo
 import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.SuccessResponse;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
 
-/**
- * Success response for `GET_LOBBY_STATUS`.
- *
- * <p>Builds a response with a single `LOBBY` block containing `ID`, `NAME` and a nested `PLAYERS`
- * collection with repeated `PLAYER` blocks (`USERNAME`, `READY`).
- */
+/** Response with lobby player listing and simple READY placeholders. */
 public class GetLobbyStatusResponse extends SuccessResponse {
-    /**
-     * Create a new response for the provided {@link Lobby}.
-     *
-     * @param context request context to use for the response
-     * @param lobby lobby domain object containing id, name and players
-     */
     public GetLobbyStatusResponse(RequestContext context, Lobby lobby) {
         super(
                 context,